1. Field of the Invention
This invention relates generally to network location services, and more particularly to a network service that maintains information sufficient to provide a near-real-time determination of proximity of affiliated mobile devices.
2. Background of Related Art
Today, every mobile cellular (e.g. CDMA, GSM, LTE, etc.) device is being located all of the time. As a mobile device moves, a cellular network does a signal hand-off between the mobile device's current controlling cell site sector and the mobile device's new cell site sector (the cell site sector into which the mobile device is moving). Signal handoff enables continuous and unbroken signaling to be maintained for a mobile device. Every cell site sector has an associated location. Hence, by inference, a mobile device's general location is known by a respective cell site.
As cellular infrastructure technology becomes deployed in greater density patterns (picocells, a.k.a., “femtocells”), a general location inferred from a cell site with which a mobile device is primarily communicating becomes higher fidelity.
Many cellular carriers are currently in the process of adding location probes to all deployed macro-cell sites. Location probes will enable carriers to maintain much more accurate location information for mobile devices located within range of these macro-cell sites.